1972 Starcraft Bassmaster - Floor

[Pretender1]

First time boat owner - first time posting. I have a 1972 Starcraft Bassmaster - 16'. After reading through multiple threads I am still confused and have what feels like a dumb question. I have taken my floor out and realized the first section of floor is 1/2" thick 52" wide x 9' in length creating only one seam - which brings me to my question. What is everyone doing to address the width? If I buy marine grade I would have to purchase 4-sheets and have four seams which i would like to avoid. All I can find right now is 5' x 10' Douglas fir that is 3/4".